A correlation between friction reduction and molecular size for the flow of dilute aqueous polyethylene-oxide solutions in pipes.
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Authors
Kinnier, John Wesley
Subjects
polymeric friction reduction
toms effect
polyethylene-oxide
pipe flow
equivalent hydrodynamic sphere
critical shear stress
polymer degradation
transition
toms effect
polyethylene-oxide
pipe flow
equivalent hydrodynamic sphere
critical shear stress
polymer degradation
transition
Advisors
Sanders, James V.
Date of Issue
1970-06
Date
June 1970
Publisher
Monterey, California ; Naval Postgraduate School
Language
en_US
Abstract
Pipe-friction factors for dilute aqueous polyethylene-oxide
solutions in pipes of nominal diameters of 1/4, 3/8, and 3/4 in. were
measured over a two decade range of Reynolds numbers. In the transition
region, the amount of drag reduction is dependent upon polymer
concentration and wall shear stress as well as Reynolds number.
For high Reynolds numbers, where the wall shear stress was high
compared to the critical value, no diameter effect was noted.
Intrinsic viscosity measurements, made on samples withdrawn from
pipe flow, provided direct evidence that polymer degradation take
place under flow conditions. Spectrographic measurements indicated
that this degradation is mechanical (and not chemical). The relative
volume of solution occupied by polymer molecules (represented
by the volume of equivalent hydrodynamic spheres) is shown to be a
dominant parameter governing the drag-reduction phenomenon for
polyethylene-oxide solutions in pipe flow. It is further shown
that the equivalent volume ratio may be used to normalize the pipe
friction factors for various concentrations of different molecular-weight species of polyethylene-oxide.
Type
Thesis
Description
Series/Report No
Department
Physics
Organization
Naval Postgraduate School (U.S.)
Identifiers
NPS Report Number
Sponsors
Funder
Format
Citation
Distribution Statement
Approved for public release; distribution is unlimited.
Rights
This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.